1. Field of the Invention
Embodiments of the present invention relate to an adapter for a memory card slot and a method of adapting a memory card slot for non-specified memory card sizes.
2. Description of the Related Art
The strong growth in demand for portable consumer electronics is driving the need for high-capacity storage devices. Non-volatile semiconductor memory devices, such as flash memory storage cards, are becoming widely used to meet the ever-growing demands on digital information storage and exchange. Their portability, versatility and rugged design, along with their high reliability and large storage capacity, have made such memory devices ideal for use in a wide variety of electronic devices, including for example digital cameras, digital music players, video game consoles, PDAs and cellular telephones.
One popular type of flash memory device is the CompactFlash® memory card manufactured by SanDisk Corporation, Milpitas, Calif. While used in a variety of different applications, the CompactFlash memory card has been adopted as the de facto standard in the professional and consumer imaging markets. While there are several reasons why this is so, including the large storage capacity and low cost per megabyte, the form factor of the CompactFlash memory card has proven to be a significant contributing factor. At 43 mm by 36 mm, the card is large enough for easy manipulation, yet small enough for convenient transport and use in current high resolution digital cameras. Professionals and consumers are comfortable with and have grown accustomed to this size memory card.
While the demand for the look and feel of the CompactFlash card is likely to continue, CompactFlash cards use a parallel bus interface which is becoming outdated. In particular, serial bus interfaces have been developed that provide faster data transfer rates and better performance. Accordingly, professionals and consumers are looking for a memory card having the look and feel of a CompactFlash, but with the speed and performance of a serial bus interface.
A few years ago, a coalition of member companies of the Personal Computer Memory Card International Association (PCMCIA) developed the ExpressCard® peripheral as a new standard for PC card technology. An example of an ExpressCard memory card 20 is shown in prior art FIG. 1. The card 20 fits within an ExpressCard slot 22 in a host device 24, which may be a notebook computer, desktop computer, or various other computing devices. In contrast to older PC cards having a parallel bus interface, ExpressCard technology uses a PCI-Express (PCIe) serial bus interface. The PCIe interface has a simple connector and eliminates the older PC card controller by using direct connections to PCIe and USB ports in the host device. As indicated above, the PCIe interface provides faster transfer rates, better performance and lower cost for the card slot implementations in host systems as compared to older generation PC cards.
Given these advantages, there are compelling technology and business reasons why the popularity of the ExpressCard standard will continue to grow. However, standard ExpressCards come in two sizes: the ExpressCard/34 is 75 mm long by 34 mm wide, and the ExpressCard/54 is 75 mm long by 54 mm wide. Both of these are significantly larger than the CompactFlash card. As such, consumers and professionals who have grown accustomed to the CompactFlash form factor may be slow to adopt the ExpressCard standard. It would therefore be advantageous to provide an adapter which allows a memory card having the size, look and feel of the CompactFlash card to be compatible with the ExpressCard standard.
It is known to provide conventional ejector mechanisms within an ExpressCard slot such as slot 22 of FIG. 1. An older type of ejector mechanism commonly employed with legacy PCMCIA cards and still in use includes an ejector button beside the slot. In order to eject a card seated within a slot, a user depresses the ejector button, which actuates a cantilever that in turn exerts an ejection force on a front surface of the card. (As used herein, the “front” of the card/adapter refers to the portion of the card/adapter inserted first into the slot and located at the rear of the slot when inserted; the “back” of the card/adapter refers to a portion of the card/adapter located at the front opening of the slot when the card/adapter is inserted).
Another type of ejector mechanism commonly used in ExpressCard slots is the so-called “push-push” ejector mechanism. While various configurations are known, in general, a spring loaded, translating pin or tab is provided at the rear and to the side of the slot. When a card is initially inserted, a front portion of the card engages the tab and translates the tab rearward against the force of the spring. At some point during the rearward motion of the tab, an actuator locks the tab in place against the force of the spring, and a frictional force of the card edges within the slot holds the card in the slot. In order to release the card, a force is again exerted by a user against a rear of the card, protruding slightly from the slot. This action again translates the tab rearward and moves the actuator from the locking position to an ejection position where the tab is released. Thereafter, the spring-driven tab ejects the card from the slot, overcoming the frictional force maintaining the card within the slot. Further details relating to an example of a push-push ejector mechanism for use in a memory card slot are disclosed in U.S. Pat. No. 7,077,671 to Su et al., entitled, “Memory Card Connector with a Push-Push Mechanism.”
The functions of ejector mechanisms may be incompatible with an adapter for use in a memory card slot. In particular, where an adapter is used in a memory card slot, pushing an ejector button or a memory card within the slot may eject not only the memory card but the adapter as well. This may be inconvenient, in as much as a user may wish an adapter to remain within the card slot while memory cards are inserted into and removed from the slot.